The BBC says the show is pre-recorded a "handful" of times

On 10 February, BBC One's Saturday Kitchen host James Martin said viewers could call in for the next week's show.

But the next instalment was recorded just minutes after the live show - too little time for callers to appear.

A BBC spokesman said it was a simple mistake and all phone profits went to charity. Premium phone line regulator Icstis has launched an investigation.

When the pre-recorded show was broadcast on 17 February, viewers were also told they could phone in to put questions to guests.

'Serious allegation'

Calls to get on the show cost a flat rate of 25p, while calls with questions cost 10p.

The BBC spokesman said: "The BBC has always made it clear to the makers of Saturday Kitchen that pre-recorded material should not be presented as live.

"It has come to our attention that the phrasing used when inviting viewers to contact the programme was ambiguous on the few occasions that the programme was pre-recorded.

"To avoid any future misunderstanding the BBC has decided that Saturday Kitchen will always be a live show from now on."

An Icstis spokesman said: "We are gathering information to see if an full investigation is required.

"Clearly any allegation a programme has encouraged the public to call under false pretences is a serious one."